The paper focuses on the implementation method of virtual impedance for grid-forming inverters and its application in microgrids. Based on the typical control strategy of the grid inverter, this paper constructs the mathematical model of the microgrid inverter, investigates the novel scheme of virtual impedance design, quantitatively analyses the influence of the system model parameters on the electrical energy output and elaborates on the physical fitting of the impedance parameters in detail. A novel virtual impedance implementation scheme for grid-forming inverters based on bandpass filters is presented, which can simulate the actual impedance of grid-forming inverters. Finally, the correctness and validity of the proposed scheme are verified through simulation. The simulation results demonstrate that the scheme can achieve the substitution of impedance and effectively enhance the system stability and the quality of electrical energy output.